Low-and intermediate-grade lateral sinus dural arterio venous fistulas: Factors affecting the outcome of endo vascular treatment over 18-year experience in a high-volume neurovascular center

BACKGROUND AND PURPOSE: Lateral sinus dural arteriovenous fistulas (LS-DAVFs) carry a higher rate of recurrence after endovascular treatment (EVT). Our objective was to investigate the independent predictors of recurrence and unfavorable functional outcome of low-and intermediate-grade LS-DAVFs after EVT.

MATERIALS AND METHODS: Retrospectively reviewed our database of prospectively collected information for all patients with low and intermediate-grade LS-DAVFs that underwent EVT from May 2004 to December 2021. Patient demographic, angiographic, treatment, and outcome were analyzed to identify independent predictors of recurrence and unfavorable outcome.

RESULTS: One hundred and seventeen patients with 117 low-and intermediate-grade LS-DAVFs underwent EVT were included in this study. The mean age of the patients was 53.0±17.5 years. Immediately complete obliteration was achieved in 103/117 (88%) patients after EVT. Clinical follow-up were available for all of 117 patients, with an unfavorable outcome rate of 5.1%. Angiographic follow-up was available in 91 patients (78%). Recurrence occurred in 16 (18%) patients and 8 (6.8%) received retreatment. Contralateral sinus severe stenosis or occlusion was an independent high-risk factor for the unfavorable outcome (OR=11.7; 95% CI: 1.9-70.9, P<0.01) and recurrence (OR=63.8; 95% CI: 10.3-396.5, P<0.01) for low-and intermediate-grade LS-DAVFs at follow-up.

CONCLUSIONS: Contralateral sinus severe stenosis or occlusion represents a stronger independent risk factor associated with recurrence and unfavorable outcome in patients with low-and intermediate-grade LS-DAVFs when the involved ipsilateral sinus was occluded after EVT. For patients with LS-DAVFs, the patency of the contralateral sinus should be considered when therapeutic decision-making.

ABBREVIATIONS: LS-DAVFs = Lateral sinus dural arteriovenous fistulas; EVT = endovascular treatment; TAE = Transarterial Embolization; TVE = Transvenous Embolization; CN = cranial nerve; CVD = cortical venous drainage.